A wide variety of devices are known for removing particulates from a gas stream. The most common form of such devices generally utilize some type of filtering means to physically entrap the particulates and thereby remove them from the gas stream. A drawback of these devices is that the filtering means must be periodically cleaned or replaced.
Another widely used type of devices for removing particulates from a gas stream is a cyclone type separator where the particulate-laden gas stream enters a cylinder or conical chamber tangentially at one or more points and exits through a central opening. The particulates, by virtue of their inertia, tend to move toward the entire wall of the chamber where they are collected. While a cyclone type separator generally operates with high efficiency, collection of larger particulates generally subjects the separator to relatively high wear due to abrasion. In addition, relatively high gas velocities are generally required.